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	hartrees
Energy at 0K	-77.283250
Energy at 298.15K	-77.283446
HF Energy	-77.283250
Nuclear repulsion energy	24.477499

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	Σ_g	3546	3394	0.00
2	Σ_g	2032	1945	0.00
3	Σ_u	3441	3294	82.03
4	Π_g	685	656	0.00
4	Π_g	685	656	0.00
5	Π_u	785	751	142.27
5	Π_u	785	751	142.27

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.611
C2	0.000	0.000	-0.611
H3	0.000	0.000	1.679
H4	0.000	0.000	-1.679

	C1	C2	H3	H4
C1		1.2211	1.0682	2.2893
C2	1.2211		2.2893	1.0682
H3	1.0682	2.2893		3.3575
H4	2.2893	1.0682	3.3575

Number	Element	Mulliken
1	C	-0.269
2	C	-0.269
3	H	0.269
4	H	0.269

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: B3PW91/LANL2DZ

States and conformations

	Computational Chemistry Comparison and Benchmark DataBase Release 22 (May 2022) Standard Reference Database 101 National Institute of Standards and Technology
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<r²>	17.085
(<r²>)^1/2	4.133

All results from a given calculation for C2H2 (Acetylene)

using model chemistry: B3PW91/LANL2DZ

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)